What is dynamic routing and how it differs from Static

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What is dynamic routing and how it differs from Static

What is dynamic routing and how it differs from Static

Certification: Cisco CCNA Routing and Switching - Cisco Certified Network Associate Routing and Switching

Routing, in a broad sense, means the exchange of packets of information among a specific nodes path within a network. Probably the most known network, and most certainly the biggest, is the internet. Each day an immeasurable amount of data is transferred from one part of the globe to the other. The amount is so huge, in fact, that, if gathered into one point, it would measure about 3 grams. However, the internet is not just some magic thing that floats around us in the air like some of us might believe, but a combination of nodes, each note holding data. The internet, in a sense, is the sharing of that data among all the devices within that network. But then comes the problem: How can you send a cat picture from PC A to PC B if between them, there are thousands of other devices? Therein lays the use of routing. Through it, that cat picture will find the best (and usually fastest) path through the network to its destination of point B. The exchange of information that happens in order to do that is huge, and is usually one node telling the others he can “reach” which other nodes he can connect to. Then, through the magic of mathematical algorithms, the path is formed, and the data is transferred. The hardware that does that exchange is usually the routers (yes like the one that feeds WiFi to your house), albeit usually one much bigger, although it may also be done by your PC, at a performance cost.

The two types of routing.

Routing can be done in two ways. Through the so called static routing (or non-adaptive routing) and dynamic routing (or adaptive routing) is a path created. The main difference between the two is that static routing is usually manually configured by someone. The phone lines of the past were such examples. There were phone lines people that would manually connect your line to the one that will lead to your destination. Nowadays that type of routing is no longer feasible, yet some small networks still use it for its few advantages over the dynamic path. Speaking of it, the main plus of the dynamic path is that it’s automated. Everything happens through algorithms, and nobody else needs to touch anything. Adaptive routing automatically creates the tables it needs to function, and can work almost autonomously (however it still needs some pre-configuration). Such type of routing is what makes the internet possible.

Static Routing

As said before, static routing sends data through a manually configured routing entry, rather than to rely on network protocols to generate paths itself. Network administrators are needed in order to create and update routing tables to be used, although there are some alternatives thanks to The Reliable Static Routing Backup Using Object Tracking (CISCO).

There are some advantages to using static routing. For one, it is much more secure, as information cannot choose its own path, but must go through a specified one. Also, static routing takes precedence over dynamic routing, and for most small networks, it is more effective as nodes no longer need to exchange routing information between them beforehand.

However static routing is not feasible on a grander scale. And, because their paths usually need to be manually configured, there appears a possibility of there being human error within the tables. Also, some static routing may prevent dynamic routing protocols to “go buggy”, not letting them work as otherwise intended. Also, any changes in the network must be properly configured.

Dynamic Routing

Dynamic routing moves to solve the problem of manually configured tables by employing the use of algorithms and protocols to automatically create and update routing tables based on network protocols, such as the Bellman–Ford algorithm. To do this, routers, or nodes continuously exchange routing information which contains information about all the other nodes that is can reach, so a routing path can be generated. Any change in the network, when found by a router, is reported to all the other nodes that that router connects to, and the tables are modified accordingly.

There are many advantages to using dynamic routing. Firstly, the tables are updated immediately, without any need for additional configuration. Also, it is best at finding the optimal route for the data to be passed by, without the implication of human error. Dynamic routing is also less expensive, as competent trained personnel needed to maintain and configure the network is not that imperative.

However, using dynamic routing also has its disadvantages. For one, static routing takes precedence over dynamic routing, and sometimes it may even cause the routing protocols on routers to not work as intended. Also, because of the need to continuously exchange information between nodes, there is increased bandwidth traffic, which may also affect CPUs and RAMs. It is also easier to penetrate a dynamic routing network, so it is also less secure.

The best of both worlds

Thankfully, dynamic and static routing do not mutually exclude one another. In fact, they can be both used in symbiosis to create the best paths and networks. While the use of dynamic networking remains almost mandatory for the World Wide Web, some nodepoints can also use static routing to minimize traffic and security attacks and issues. For example a company office may use a static network that, at one point, connects to a dynamic network providing internet access. There’s no reason why we shouldn’t have both cookies and milk after all, even if this isn’t the dark side.

Both routing methods have their advantages and disadvantages, and not using them in combination to get the best result would be rather strange, so that’s why we do it.

What is dynamic routing and how it differs from Static

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